FIG 2.

PrrF regulates expression of the sodB and antR target mRNAs. PAO1 and the ΔprrF1-prrF2 (ΔprrF) strain, transformed with either pUCP18, pUCP-prrF-235 (ΔprrF/WT strain), or pUCP-prrFΔH-235 (ΔprrF/ΔH strain), were grown overnight in DTSB to deplete intracellular iron stores, subcultured into M9 medium to a final an optical density (600 nm) of 0.08, and then grown for an additional 8 h. RNA was extracted from aerobic and microaerobic cultures and analyzed for expression of sodB (A) and antR (B) expression as described in Materials and Methods. Complementarity that was previously identified (21) between the PrrF sRNAs and the sodB and antR mRNAs is shown above each graph, and the Shine-Dalgarno and/or translational start sites of the mRNAs are underlined. Error bars indicate the standard deviations from six biological replicates. Significance was determined by a two-tailed Student's t test comparing results for each strain to the result with the wild-type vector control (**, P < 0.001).